Conditions inside many gaols were dreadful. Held without segregation "according to sex or classification" men, women and children were kept in filthy damp communal cells. Drinking, gambling and immorality were rife and disease widespread. Outbreaks of "jail fever" (typhoid) killed many prisoners, jailers and judges.

In 1773 John Howard began investigating prison conditions. Horrified by what he saw he suggested the state pay gaol-keepers a regular wage and that prisoners be kept in separate cells and given "useful work". In 1774 two acts were passed to improve prison hygiene and stop discharged prisoners having to pay their gaolers to be released.

Prisons remained under the control of local authorities until 1877 when the English and Welsh prison system was brought under the control of the newly formed Prison Commission. Fifty-three prisons closed including those at Anglesey, Brecon, Cardiganshire, Flintshire, Merionethshire, Montgomery and Radnorshire.

Criminal Prisons in London and Scenes of Prison Life by H. Mayhew and J. Binny, first published in 1862.)